951cro

Hello everyone, I’m a Croatian guy living in Germany with love towards old sports cars, and a few months I bought myself a 1986 951 project car.

I knew the car had a problem, which was described by the previous owner as a bad head gasket. The car was in a standstill for 5 years and as the oil was completely mixed up with water it was a reason enough to believe it probably is the head gasket. Unfortunately for me, after removing the head (and all the other parts that had to go in order to come to the head), we found the gasket in perfect condition. After reading through many forums and threads, I decided the next thing to check will be the oil cooler, as it is also a common spot of oil mixing with water. Seemed to be in perfect order, it’s gasket was also already replaced some years ago, by the looks of it.
The next thing we noticed was there was also water-oil in the many different hoses around the turbocharger, so the mechanic ,in whose workshop I am working on the car, suggested to remove the turbo for inspection.
And now it gets really interesting..
Upon removing the Turbocharger, a large amount of the milkshake started pouring out of it. Also, the intercooler was completely filled with it which explains why the car had no power: the air couldn’t even come to the engine.

Both the turbo and the cylinder head were sent to machine shops for inspection and refurbishment, and even though some faults were found, none are something that would cause the water and oil to mix and also to enter the air intake system.

What I did notice, however, is that the crankcase breather hose (which I assume is coming from the air-oil separator) coming in just before the turbo inlet, was also filled with the milkshake, and I currently see that as the only way that the milkshake could have entered the turbo, and was then pushed by the turbo to the intercooler. The question is, what is causing the water and oil to mix in such amounts and what’s pushing them to the parts where there should normally only be air.

I’m hoping someone here can help me with this puzzle, as I’ve run out of ideas.

Thank you in advance

Lorka

— In the attached photo, blue represents hoses before the turbocharger where milkshake was present

951Tom

A couple things came to mind after reading your post. Hope this helps!

1) There was a TSB issued (#9105 dated May 17,1991) for the short connector pipe on the oil cooler housing. The original could allow water & oil to mix. See my post in the link below for the updated connector pipe part #.
https://rennlist.com/forums/924-931-...r-housing.html

2) Somehow your engine ingested water thru the intake snorkel tube.

951cro

Hi 951Tom,

Thank you for the reply!

I have installed a new set of gaskets for the oil cooler, and inside the set was the updated version of the pipe that is mentioned in that thread (same length on both sides). So if that was causing the mixing, that's pretty much finished?

Could you please specify where the snorkel tube is and what is it's function on the 944? (the only snorkel tubes I know of are on Offroad vehicles, for crossing deep water)

951Tom

The snorkel tube supplies cold air to the air filter box & engine. It mounts to the open circle just to the right of the coolant reservoir.